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41.
Robert Weis Marcel Kaiser Reto Brun Robert Saf Werner Seebacher 《Monatshefte für Chemie / Chemical Monthly》2006,137(10):1365-1374
Summary. 4-Aminobicyclo[2.2.2]octan-2-ones and -ols showed activity against the causative organisms of East African sleeping sickness
and Malaria tropica. Several imino derivatives of the ketones were more active. Now hydrazono analogues and 3-hydroximino
derivatives of the ketones and alcohols were synthesized. The structures of the obtained isomers were elucidated by NMR spectroscopy.
A single phenylhydrazone exhibited quite good antitrypanosomal activity in the range of already known imino analogues. 相似文献
42.
Robert Weis Marcel Kaiser Reto Brun Robert Saf Werner Seebacher 《Monatshefte für Chemie / Chemical Monthly》2006,31(6):1365-1374
4-Aminobicyclo[2.2.2]octan-2-ones and -ols showed activity against the causative organisms of East African sleeping sickness
and Malaria tropica. Several imino derivatives of the ketones were more active. Now hydrazono analogues and 3-hydroximino
derivatives of the ketones and alcohols were synthesized. The structures of the obtained isomers were elucidated by NMR spectroscopy.
A single phenylhydrazone exhibited quite good antitrypanosomal activity in the range of already known imino analogues. 相似文献
43.
Dynamical Behaviour of Linear Molecular Anions in the Hydrogensulfides of Sodium, Potassium and Rubidium: Differential Scanning Calorimetry, X-ray and Neutron Diffraction Hydrogensulfides of the alkali metals M ? Na, K, Rb were prepared in autoclaves by the reaction of the corresponding metals with H2S and D2S, respectively, in the temperature range from 50°C to 150°C. Differential scanning calorimetry, X-ray and neutron diffraction methods reveal that both, the HS?-and DS?-compounds occur in three crystalline modifications with HT ? high-, MT ? medium- and LT ? low-temperature form: The temperatures and enthalpies for the changes of modifications of the H- and D-compounds are given and the atomic arrangements revealed mainly by neutron diffraction data are discussed, in relation to, for example, size of cations. 相似文献
44.
C D Weis 《Helvetica chimica acta》1968,51(7):1572-1581
A simple synthesis of tetrachlorophenanthrene starting from DDT has been realized. 1,1,1,2-tetrachloro-2,2-bis-(4-chlorophenyl)-ethane (I) and its rearranged product 1,1,2,2-tetrachloro-1,2-bis-(4-chlorophenyl)-ethane (V) and other analogs substituted by halogen in the para-position undergo a cycliarylation yielding 3,6,9,10-tetrahalogenophenanthrenes. Partial dechlorination of this tetrachlorophenanthrene yields 3,6-dichlorophenanthrene. Oxidation gives 3,6-dichloro-9,10-phenanthrenequinone, and chlorosulfonation leads to 3,6,9,10-tetrachloro-2,7-bis-(chlorosulfonyl)-phenanthrene. The mechanism of this cyclization reaction in presence of LEWIS acids is discussed and compared with the cyclization of DDT derivatives to yield fluorenones. 相似文献
45.
46.
X-ray, I.R., and Raman Data of Strontium Polysulfides The strontium polysulfides SrS2, SrS3A, and SrS3B were studied in terms of preparation, thermal decomposition, and phase transition. The i.r. and Raman spectra of the strontium polysulfides as well as the normal coordinates of the phonon modes are presented and discussed in comparison with the respective barium compounds. From the spectra it is shown that S32? entities are present in SrS3A as in SrS3B. 相似文献
47.
Mulligan A Lane I Rousseau GB Hecht L Johnston SM Lennon D Kadodwala M 《Chemical communications (Cambridge, England)》2004,(21):2492-2493
Using a novel non-linear optical technique enantiomeric excess within a translationally disordered overlayer on a metal surface has been monitored for the first time. 相似文献
48.
Yiyi Weng Xingxing Ding Joo C. A. Oliveira Xiaobin Xu Nikolaos Kaplaneris Meijie Zhu Hantao Chen Zhuo Chen Lutz Ackermann 《Chemical science》2020,11(34):9290
There is a strong demand for novel native peptide motifs for post-synthetic modifications of peptides without pre-installation and subsequent removal of directing groups. Herein, we report an efficient method for peptide late-stage C(sp3)–H arylations assisted by the unmodified side chain of asparagine (Asn) without any exogenous directing group. Thereby, site-selective arylations of C(sp3)–H bonds at the N-terminus of di-, tri-, and tetrapeptides have been achieved. Likewise, we have constructed a key building block for accessing agouti-related protein (AGRP) active loop analogues in a concise manner.An efficient method for peptide late-stage C(sp3)-H arylations assisted by unmodified side chain of asparagine (Asn) without any exogenous directing group has been reported. 相似文献
49.
E. Burestedt J. Emnéus L. Gorton G. Marko-Varga E. Domínguez F. Ortega A. Narváez H. Irth M. Lutz D. Puig D. Barceló 《Chromatographia》1995,41(3-4):207-215
Summary A fully integrated screening system for phenolic compounds was developed incorporating on-line solid phase extraction, fractionation and biosensor detection. Two different types of biosensors, solid graphite and carbon paste electrodes incorporating the enzyme tyrosinase, were compared and used in the screening system. Interfacing of the solid phase extraction and fractionation with the biosensor detection was given special attention since the biosensors were not compatible with the organic modifier used for desorption of phenols from the solid phase extraction step. The system was validated with conventional analytical techniques. Surface water samples from the Ebro river were spiked with 1,10, and 25g L–1 of catechol, phenol,p-cresol, respectively. Three out of seven samples were spiked and the correct samples were identified, containing phenols equivalent to the spiked concentrations. 相似文献
50.
The oxidation of 2,6-dichloro-3-benzylpyridines and bis(2,6-dichloro-3-pyridyl)methanes, respectively, was accomplished using chromic trioxide in a highly acidic medium. The synthesis of several phenyl-3-(2,6-dichloropyridyl)ketones and of bis(2,6-dichloro-3-pyridyl)ketone are reported. 相似文献